Fenestrated asymmetric intracardiac device for the completion of total cavopulmonary anastomosis through cardiac catheterization

ABSTRACT

Fenestrated Asymmetric Intracardiac Device for the completion of total cavopulmonary connection through cardiac catheterization, having a bifurcated tubular conduct, constituted by two portions ( 1, 2 ) both made of a tubular mesh covered with an impermeable polymer. Upper end ( 5 ) of first portion ( 1 ) is progressively flattened to a substantially oval shape, with progressive cross sections of an equal area.  
     First portion ( 1 ) presents at least a lateral fenestration ( 5 ) which is selectively obturable. Second upper portion ( 2 ) bifurcates into two divergent branches ( 7, 6 ) and backwards forming with respect to the longest branch a deformed “Y”, of which: branch ( 6 ) is the longest and is introduced into the left pulmonary artery, while branch ( 7 ) is shorter and lodges into the right shorted pulmonary artery. The device defines a connection between the inferior vena cava and pulmonary branches, establishing a physiological distribution of the blood flow in both lungs.

THE FOLLOWING TABLE SHOWS DIFFERENT CHDS THAT NEED SURGICAL TREATMENT.Congenital Heart Disease with Univentricular Physiology

-   Single ventricle-   Tricuspid atresia-   Hypoplastic left heart syndrome (HLHS)-   Pulmonary atresia with intact septum and hypoplasic right ventricle-   Transposition of the great vessels, with noncommitted ventricular    septal defect and small right ventricle.-   Double outlet right ventricle and poor anatomy-   Criss cross heart-   Congenital right ventricular hypoplasia-   Ebstein's malformation

Most of these CHDs need a sequential treatment strategy. Some of them(such as hypoplastic left heart syndrome) require a special therapeutic,whose end point is common to all.

When the patient born with single ventricle (classic CHD of thispathology) and stenosis or pulmonary atresia that hinder from pulmonaryflow, in order to maintain a proper oxigenation, a prompt modifiedBlalock-Taussig anastomosis should be performed with a prosthesis tubeof 4 mm between the subclavian artery and the homolateral pulmonarybranch, usually on the left side.

If there is not pulmonary stenosis, a banding of the pulmonary artery tonarrow the lumen, to limit the flow and the pressure transmitted to thepulmonary circuit, should be performed. This prevents the development ofpulmonary hypertension which would prevent the patient from advancingtowards the next steps.

Fenestrated Asymmetric Intracardiac Device for the Completion of TotalCavopulmonary Anastomosis Through Cardiac Catheterization

The aim of this Fenestrated Asymmetric Intracardiac Device is tocomplete the Total cavopulmonary anastomosis through cardiaccatheterization.

Intended Use of the Fenestrated Asymmetric Intracardiac Device

To be used in pediatric cardiologic interventions, more specifically tocorrect specific congenital heart disease in hemodynamic interventions.

Former State of the Art—Physiology and Univentricular Therapeutics

There are different congenital heart disease (CHD) with only one workingventricle available, so this disability forces to design a therapeuticstrategy which allows to develop a special hemodynamic model.

These cases are present in newborns with this cardiac malformation andit is absolutely necessary to correct it by means of surgery.

During the last decades different techniques have been introduced forthe sequential preparation of the circulatory system, with the final aimof connecting the venous blood that comes from the heart through thesuperior and inferior vena cava with the pulmonary circuit, allowing theoxygenation of blood.

This involves performing a bypass to the right ventricle, because thenon-existence or rudimentary structure of this CHD does not allow toperform its -force pump function towards pulmonary circulation.

The target is to maintain the blood flow through a minor circuit withthe pumping function of the only active ventricle. This circuit shouldhave a low resistance to the flow, without obstruction sites, so thatblood can flow properly, even if it is not pumped with “unnatural rightheart venous pathways”.

Under any of the two conditions described above, at the age of 6 or 8month, patients should be subjected to a Bidirectional Glenn procedure.This procedure consists of the separation of the superior vena cava(SVC) from the right atrium (RA) and its connection with the rightpulmonary branch. In this way all the venous flow of the superior halfof the body will flow directly to the pulmonary artery (PA) to becomeoxygenated without coming into the heart. This is performed at this agebecause the head and the superior half of the body represent the 55% ofthe venous return. This is an open heart procedure with cardiopulmonarybypass (CB).

The last step is to complete the total cavopulmonary connection (TCPC)at the age of 3 or 4 years old, by carrying the inferior vena cava flowto the pulmonary artery under cardiopulmonary bypass (CB) too. Thesurgical techniques have been substantially modified in the lastdecades, specially in this phase. Since the early Fontan-Kreutzerprocedure, which consisted of joining the right atrium to the rightpulmonary branch (atriopulmonary anastomosis) up to the currentanastomosis with extracardiac tube between SVC and PA, severaltechniques have been tried.

This last technique consists of the IVC anastomosis to the rightpulmonary branch (RPB) with the interposition of a Gore-Tex™extracardiac prosthesis tube with a fenestration or hole in the RA as“discharge” in order to secure the postoperative cardiac output.

At this phase, the so-called “Total Cavopulmonary Connection”(TCPC) isfinished. Lately, some attempts have been made by using a covered stentwith a interventional catheterization to finish this last phase, and soavoid a new surgery, simplify the technique, minimize the risks as wellas the side effects of EC.

These stents have an expandable tubular mesh made of differentmaterials, such as a platinum-iridium, nickel-titanium, stainless-steelmesh and covered with an impermeable polymer, like expandedpolytetrafluorothyelene (PTFE). With these devices, after performing theBidir ctional Gleen procedure, IVC is connected to SVC. As well TCPAprocedure with extracardiac tube as well as the procedure with thecurrent stents have the inconvenience of supplying an unbalanced flow tothe pulmonary circulation. Current stents have one or severalfenestrations which allow the “discharge” of blood from the circuit, ifthe hemodynamic condition is not the best, allowing a right to leftshunt at atrial level, so as to maintain the postoperative cardiacoutput These openings or holes need to be closed or sealed when thepatient hemodynamic condition allows to do so.

To show a better reference frame of the former state of the art, beforethis invention, FIG. 1 shows schematically a heart which suffers fromthese CHDs, before the Glenn procedure, and in the FIG. 2 this sameheart after the Glenn procedure.

The following acronyms are used in both figures:

-   -   RPA Right pulmonary artery    -   LPA Left pulmonary artery    -   SVC Superior vena cava    -   IVC Inferior vena cava    -   SHV Hepatic vein    -   Ra Right appendage    -   RA Right atrium    -   TV Tricuspid valve

The following are bibliographical references of these known more recenttechniques:

Surgical Preconditioning and Completion of Total CavopulmonaryConnection by Interventional Cardiac Catheterization: A New Concept,(Heart 1996; 75: 403-409).

Through this technique the field to complete by catheterization thetotal cavopulmonary connection of high risk patients is carried outduring the Glenn procedure.

A left banding is done between RA and SVC, setting a Gore-Tex™ tube with3 up to 7 perforations (multifenestrated) inside RA. During the nextintervention, the banding is dilated with or without a Palmaz stentbetween SVC-AD, and the fenestrations are closed with Rashkind devicesof 17 mm, used for the closure of the patent ductus arteriosus. If it isnot possible to perform this technique, a covered stent inside aGore-Tex™ tube is placed.

A Novel Technique for Establishing Total Cavopulmonary Connection: FromSurgical Preconditioning to Intervention Completion, (J Thorc CardiovascSurg 2000; 120; 1007-9).

This technique contemplates the experimental settlement of a cavo-cavalanastomosis with a covered stent through cardiac catheterization.Previously, a side to end anastomosis between SVC and distal RPB withPTFE should be performed. SVC is left banding in its joint with RA. Thenext procedure is to introduce, via endovascular, a stent graft from theright internal jugular vein, placing it through the SVC banding, betweenSVC-RPA joint and IVC over the hepatic vena end. Then the pulmonarycava-cava artery anastomosis is completed.

Effect of Baffle Fenestration on Outcome of the Modified FontanOperation, (Circulation 1992; 86:1762-1769).

This technique shows the benefits of fenestration in the Fontanprocedure in patients of high risk. This Study compares a group of 91patients in which a fenestration of 4 mm has been left in theintracardiac tube with 56 patients without fenestration. It wasconcluded that the fenestrated tube is associated with a low mortality,less incidence of pleural effusion and less days in hospital.

Up today none of these interventions have shown optimal outcomes becausein the long term a number of patients need different interventions.

From the age of 6 approximately, the percentage of systemic venousreturn, which is kept up to the adult age, is reached. The 35% of thepulmonary flow of a healthy adult without CHD is supplied by SVC and the65% by IVC. The right lung, anatomically bigger, should receiveapproximately 55% of blood and the left lung, smaller, 45%. This impliesa flow division from the IVC in 20% of the total (30.7% flow from IVC)that should run to the RPA, while the 45% left runs to the LPA.

With the CHD corrective techniques currently known, it is not alwaysfeasible to guarantee a proper division of the pulmonary blood flow,resulting in a deficient supply according to the technique used in oneor the other lung, usually the left one.

Another problem of the known corrective techniques arid devices of theCHDs mentioned above and which can result in serious inconveniences isthe IVC transversal section in the grown up children which has anaverage of 18-20 mm, while the PA has an average diameter of 10-13 mmapproximately. The known techniques and devices resolve this problem byconnecting with a suture the superior extreme of the extracardiacconduit to the PA, and crushing it, which transforms a theoreticallyround section into a theoretically elliptical transversal section,resulting in an area decrease, and so increasing the flow resistance, ifthe speed of blood flow is reasonably constant.

The last problem is the longitudinal dimensions in case the device isintracardiac, because not all the patients anatomies have the samedimensions and so the device should be adapted to the somatic growth.

OBJECT OF THIS INVENTION

The main target of this invention is to obtain a covered stent orendoprostheses device to complete the total cavopulmonar connection oranastomosis through a cardiac catheterization procedure.

This device should be implanted in procedures performed in those CHDswhich need univentricular correction. Previously, an anatomicalpreparation during the Bidirectional Glenn procedure should be done.

An intracardiac device is another aim of this invention, which allows abest distribution of the blood flow dynamics, being able to lead between30 to 35% of the blood flow from the IVC to the RPA and between 65 to70% of the blood flow to the LPA, establishing a physiologicaldistribution of the blood flow in both lungs, which the previousBidirectional Glenn procedure brings to the right lung.

One of the aims of this invention is a device of covered stent orendoprostheses type which allows to stop the blood flow from thepulmonary artery trunk (in the case of banding of it) or to close theBlalock-Taussig anastomosis (in stenosis or pulmonary atresia cases).

Another aim of this invention is an intracardiac device whosetransversal sections allow to compensate the shape change (flattening ofthe transversal section) and to obtain a reasonable constant transversalsection.

The aim is an intracardiac device invention which allows adaptation andcompensation of the existing dimensional differences in the RA indifferent patients.

The aim is the invention of a device which allows to conduct the bloodfrom the IVC to the pulmonary artery in its join with the trunk and thepulmonary right branch.

The aim is the invention of a device which allows to discharge the bloodfrom the fenestration towards the RA in non ideal cases (“high riskpatients”).

The aim is the invention of a device which allows the physiologicaldistribution of the pulmonary flow matched with the Bidirectional Glennprocedure, improving the existing models.

The aim is the invention of a device which allows the treatment of thepulmonary tree distortion, decreasing the total resistance.

The aim is the invention of a device is to set a blood flow with thesmallest power losses with regards to the existing one.

The aim is the invention of a device is to contemplate the heart somaticgrowth by its left convexity curvature and the re-expansion of itsdiameters.

And, the final aim is the invention of a device to derive the blood fromthe liver (IVC) towards both lungs, which is a physiological importantcircumstance which avoids the development of pulmonary arteriovenousfistulas.

BRIEF DESCRIPTION OF THE INVENTION

The Fenestrated Asymmetric Intracardiac Device for the completion oftotal cavopulmonary connection through cardiac catheterization ischaracterized for having a bifurcated tubular conduct, whose parts are:a first inferior portion and a second superior portion, being bothportions, one after another, in accordance with the same axis which iswarped in the space of the unique conduit.

The first portion is a tubular mesh covered with an impermeable polymerwith a curvature of between 35° and 45°, having this first portion inits inferior end, a transversal section, substantially circular, with adiameter between 16-20 mm, while in its superior end the first portionhas a transversal section, progressively flattened and with asubstantially oval shape, being the transversal sections along the axisof the same area.

The lateral of this first portion presents at least a fenestration whichis selectively closure and which connects the interior of this conduitwith the exterior. The inferior end of this first portion can present amesh structure without polymeric cover, defining an end of permeableconduit, This first inferior portion is followed by the second superiorportion which has a tubular mesh covered, at least in some parts, by animpermeable polymeric material and with transversal sections, along thewarped axis, being more oval up to get a smaller diameter of theellipse, between 10-13 mm.

Both transversal sections are substantially of the same area aftergetting the second portion of this section whose diameter is smallerthan 10-13 mm, it bifurcates into two branches, one of the branchesbeing longer and the transversal sections circular with a diameterbetween 10-13 mm and prolonging the warped axis with a posteriorinclination, while the other branch is projected after the shape of ashort appendix of a transversal section substantially circular with adiameter of 10-13 mm and obliquely divergent and backwards forming withrespect to the longest branch a deformed “Y”; being the length of thefirst portion between 60-75 mm, while the longer branch of the secondportion is between 18-25 mm long, and the length of the short bifurcatedaxis is between 4-8 mm defining the short appendix in its bifurcationwith respect to the longer longest branch with a wall portion whichfaces between 50%-70% of the blood flow that runs through the maintubular conduct from its inferior end. The inferior end of the firstsection defines a connection between the inferior vena cava and thehepatic venous, being this tubular conduct lodged inside the rightatrium and anchored in the joint of this structure and the IVC, whilethe longest section is lodged inside the left pulmonary artery stating arelation of close contact with the internal walls and determining anobstruction of the pulmonary artery trunk, while the branch of the shortlength bifurcation is lodged inside the source of the right pulmonaryartery.

PREFERRED EXAMPLES TO PERFORM THIS INVENTION

The following sketches together with their description will illustratethe examples of the performance of this invention.

This example of performance should be understood as one of the manypossible constructions of the invention, not limiting its use, includingin its protection boundary the possible equivalent means described,being the spectrum of this invention determined by the first claimsattached in the Claims Chapter.

Likewise, in this figures, the same references identify the same orequivalent means.

FIG. 1, shows schematically a heart portion with the congenital CHD,depicted above and presents only the influence area related to RA.

FIG. 2, shows the same heart portion of FIG. 1 which has undergone theGlenn procedure and banding in pulmonary artery.

FIG. 3, shows a view in lateral elevation of one of the possibleconstructions of the invention device.

FIG. 4, shows a construction of the device in detail.

FIG. 5, shows the same device turned 90%. around its axis.

FIG. 6, shows schematically the areas relation in the transversalsection with the projection of determined sections and illustrating theconcept of the division of the blood flow which runs up in IVC in thedevice bifurcation.

FIG. 7, shows the invention device lodged inside the FIG. 2 heart.

FIG. 8, shows the AA cut of FIG. 3 and,

FIG. 9, shows the BB cut of FIG. 3.

FIG. 1 shows schematically a RA of a heart with a characteristiccongenital heart disease in its previous condition, before a Glennprocedure.

FIG. 2 shows the same RA after the Glenn procedure, which consists ofthe sectioning of SVC, suturing the superior section 1SVC to the RPAbranch, joining s1, while 2SVC, which is connected to RPA is sutured andclosed with s2 suture. Before a banding has been practiced in pulmonaryartery.

With this intervention the heart is ready for the next interventionsabove depicted. The invention contemplates an asymmetric intracardiacdevice which defines a covered stent or endoprostheses form by a firstinferior section (1) and a second superior section (2). Both sections(1,2) are one after the other according to the same warped axis X-Xprepared in the same space forming a unique conduit.

The first inferior section (1) is a mesh, like a stent mesh, that is tosay a mesh made of metallic threads joined or welded and covered with animpermeable polymeric material, such as polytetrafluorothyelene (PTFE)The inferior section (1 a) of the inferior portion (1) is preferably notcovered and is inserted inside the IVC, allowing the mesh portionwithout cover to collect the blood which comes from the VSH.

There can be two different completions with respect to the constitutionof these two sections (1,2). In one of these constructions the inferiorsection (1) is axially inserted inside the second section (2), thejoining area is shown in reference (3) and FIG. 4 shows this in detail.This construction allows the Interventional Cardiologist to make atelescopic adjustment of the device total length and to adequate it tothe anatomy of each patient, moving section (1 b) which is insertedinside the inferior end (2 a) of the superior portion (2)

The other possible completion is the one in which the inferior section(1) is followed by the superior section (2) forming only one piece.

From the material point of view, this device can be formed by a samemesh in both sections (1,2) or the inferior portion (1) can be made of amore rigid mesh, while the superior portion (2) can be made of a moreflexible and soft mesh. So it is important to say that the device of theinvention can present a unique mesh of equal resistance along thedevice, or a mesh with different rigidity and elasticity.

The first portion (1) includes a curvature between 35°-45°, having thefirst section in its inferior end (1 a) a transversal sectionsubstantially circular with a diameter between 16-20 mm, which is shownin FIG. 8, where it can be seen the AA cut of FIG. 3, while in itssuperior end this first section presents a transversal sectionprogressively flattened and with a substantially oval shape, which isshown in FIG. 9 and showed by BB cut in FIG. 3.

One of the important characteristics of this invention in one of itspreferred constructions is the transversal sections along the XX axiswhich have substantially the same area from the inferior end (1 a) untilit gets to an area (4) bellow the bifurcation described, precisely,having to join in this zone, when the device with the pulmonary arteryjoins with the RPA branch, whose average diameter is 12 mm, it must havean oval or elliptic section whose smallest diameter according to the Yaxis of FIG. 9 is equivalent to 12 mm, which allows to rest the biggestaxis of the RPA, and so manage to maintain a transversal section withthe same area.

The lateral of this first section (1) presents at least a fenestration(5) of 4 mm of diameter, with selective closing, which communicates theconduit interior with the exterior of it.

After reaching this second section (2) a high equivalent to the section(4) in FIG. 3, this second section (2) bifurcates in two branches. Oneof these branches is longer and with transversal section which aresubstantially circular with a diameter between 10-13 mm and followingthe warped axis XX, indicated in reference (6), introducing it in atight-fitting way inside the LPA, establishing an hermetic tightrelation with the internal walls, and closing the pulmonary arteryentrance.

The other branch (7) is projected in the shape of a short appendix oftransversal sections, substantially circular, with a diameter of 10-13mm and obliquely divergent with posterior inclination, forming withrespect to the branch of major length, a distorted Y, inserting thisshort branch (7) into the beginning of the RPA.

In the device the first section (1) length is between 60-75 mm while themajor length branch (6) of the second section is between 18-25 mm long,an the length of the short bifurcated appendix is between 4-8 mm.

Another important aspect of this invention is that it provides adistribution of the RPA and LPA flows balanced according to thephysiological model.

For these the invention ponders that the branch of major length (6)should be the followed by of the warped axis XX, but from thisbifurcation the transversal section (6) is substantially circular with adiameter that oscillates around 12 mm. Originated in an elliptic tubularconduct in (4) with an area equivalent to a circle with an averagediameter of 18 mm, the transversal area (6) is notably smaller than thetransversal section (2) in zone (4), so the short appendix (7) which isborn in this area (4) is projected from the transversal area equivalentwith a circumference of an average diameter of 18 mm. The transitionbetween these two transversal areas is surpassed preparing the appendix(7) of the wall (8) substantially perpendicular to the blood flow whichruns through (1,2), forcing part of the flow to divert through (7) whenit collides with (8).

In another words, the short appendix (7) in its bifurcation with respectto the branch of major length (6) defines a wall portion (8) which facesbetween 50%-70% of the projected one, which runs through the blood flow,which runs up in the tubular conduit (1,2) from the inferior end, asindicated by the arrows in FIGS. 3 and 6. This short appendix can becovered, or can be a mesh without coating.

In another construction of the invention, is contemplated the branch (6)of the bifurcation which has a transversal section slightly decreased toits free end, with the aim of being applied in cases in which it isnecessary to limit in a small average the blood volume towards LPA, andto increase the flow towards RPA, according to the InterventionalCardiologist's criterion.

FIG. 5 shows the device of FIG. 3, projected with a lateral elevationfrom its left side. It is emphasized that the XX axis is warped in thespace, and the end (9) of the branch (6) runs backwards like branch (7).It can also be seen, too in this figure that the transversal sections ofsection (2) are flattened up to gain a smaller diameter compatible withLPA diameter.

FIG. 6 is an idealization which shows the area relationships between thedifferent device branches, showing the sections which form a slightlateral perspective, as if they have straight axes and constant andcircular transversal section.

This situation allows to establish that the XX axis is aligned withsection (6) of the bifurcation, which is moved towards a lateral of thedevice, while the branch (7) of the same bifurcation is aligned withanother MM axis. These two axes represent the blood flows separation andflowing through (6) and (7). In the bifurcation quoted above, it isimportant to stress that the portion (2) shows a transversal area (10),belonging the transversal areas (11) and (12) to sections (6) and (7).It can be seen that areas (11,12) are smaller in magnitude that area(10), in a proportion substantially coincident with the flow rate, whichderives from branches (6) or (7).

Discussion about Technique Application of the Current Invention

FIG. 7 shows the device of invention placed inside RA, according to oneof the several possible techniques, not being this technique neitherunique nor exclusive. This technique in attaching the appendage end (Ra)with the pulmonary trunk neck with the RPA orientated towards the LPA.This attachment can be made suturing the appendage end and then making apuncture from inside the RA so that to give way to the devicebifurcation (6,7) or suturing a short conduct (Con) connecting the Rawith the RPA, puncturing or cutting and passing the device sectionthrough that conduct (See FIG. 7).

The connection site is the joint, established before hand by surgery,between the right appendage (Ra) and the right pulmonary artery (RPA)close to the pulmonary trunk.

This connection avoids the sinus node and the complication caused byconduction disorders. The surgery technique, during the previous Glennprocedure, should contemplate a reinforcement with Gore-Tex through ananastomosis of both anatomical references and attaching the surface ofthe superior right appendage with the inferior one of the proximal rightbranch. The “floor” of the right branch will open freely and theappendage “vault” will divide into cross sections with an elliptic areaand then these incisions should be sutured leaving in its centralsection a radiopaque gost.

In its unified version, the device is auto expandable, it releases whenthe sheath is withdrawn, when the device is deployed from its distal end(API). It will installed according to the anatomical features, up tobifurcation site. The deployment device arm mechanism (7) or the rightbranch of the bifurcation is by elastic recovery of its shape andorientation. This happens because it is perpendicularly telescopedinside the device tubular body. The primary anchorage is caused whenboth branches are intubated. The secondary anchorage is at IVC level.

In its version of two bodies, the distal or superior portion (2) is autoexpandable and is inserted in the pulmonary branches, as depicted above.The inferior or proximal section (1) the one that have the fenestration,can be made of a more rigid material, or with a less flexible, and canbe deployed with a balloon, by inserting it inside the superior portion(2).

1. Fenestrated asymmetric intracardiac device for the completion oftotal cavopulmonary anastomosis through cardiac catheterization,characterized for having a bifurcated tubular conduct, which is formedby a first inferior section and a second superior section, being bothsections one after the other, according to a same warped axial ace inthe space form by a conduit section. The first section is a tubularmesh, covered at least in some parts of it by an impermeable polymerwith a curvature between 35°-45°. This first section in its inferior endhas a transversal section, substantially circular, with a diameterbetween 16-20 mm, while in the superior end of this first section, ithas a transversal section progressively crushed and with a substantiallyoval shape, being the transversal sections along the quoted axes whichsubstantially has the same area; the lateral of this first sectionpresents at least a fenestration selectively closure, which communicatesthe interior of that conduit with the exterior of it. This firstinferior section is continued by the second superior section, which hasa tubular mesh covered with, at least in some parts, an impermeablepolymeric material and transversal sections, along the warped axis,growing oval up to get a diameter smaller than the ellipse, between10-13 mm. The transversal sections are substantially equal in area.After reaching this second section, the diameter section smaller than10-13 mm, this section bifurcates in two branches, being one of thesebranches longer and the transversal sections substantially circular andequal in area. When this second section reaches the smallest areasection (10-13 mm), it bifurcates in two branches, being one of thesebranches longer and the transversal sections substantially circular witha diameter between 10-13 mm and prolonging the warped axis, while theother branch is projected into a short appendix of transversal sectionwhich is circular, with a diameter between 10-13 mm and obliquelydivergent, forming with the longest longitude major branch a distorted“Y” whose branches are directed backwards. Each of these branches has amesh of thread, which are partially covered by an impermeable polymericmaterial and they form a unique body with the second superior section,being the section longitude between 60-75 mm, while the longest branchof the second portion is between 18-25 mm long, and the longitude of theshort bifurcated appendix is between 4-8 mm; defining the short appendixin its bifurcation with regard to the major longitude branch of the wallthat faces between 50%-70% of blood which runs up through the areaprojected by the tubular conduct from its inferior end. The firstsection inferior end determines a connection with the inferior vena cavaand the hepatic vena, being this tubular conduct, which is formed by theprimary and secondary sections, lodged inside the right atrium, whilethe major longitude section of the bifurcation is lodged inside the leftpulmonary artery, setting a close relation with the inner walls and anobstruction with regard to the main pulmonary artery, while the branchof the minor longitude bifurcation lodges the origin of the rightpulmonary artery.
 2. Fenestrated asymmetric intracardiac device,according to claim 1 state this device is characterized by a firstinferior section and a second superior section, which form a uniquetubular body made, at least, of a series of threads forming a mesh. 3.Fenestrated asymmetric intracardiac device, according to claim 1, thisdevice is characterized by a first inferior section, which has a meshspan. This mesh span is independent of the second superior section,being this first section axially deployable and it can be set into thesecond section, defining a tubular body, whose longitude can varyselectively.
 4. Fenestrated symmetric intracardiac device, according towhat is stated in claims 1,2 and 3, this device is characterized by afirst inferior section, which has a mesh made of more resistantfilaments than the second section, determining a first inferior sectionof less flexibility with respect to the second superior section. 5.Fenestrated asymmetric intracardiac device, according to what is statedin claims 1, 2, 3 and 4, this device is characterized by the inferiorend of this first section, which has a mesh structure without polymericcover, defining a tubular end, which is permeable by the blood flow thatruns up through the inferior vena cava and the hepatic vena. 6.Fenestrated asymmetric intracardiac device, according to claim 1, thisdevice is characterized by a major longitude branch of the bifurcation,which is formed by a mesh made of threads, which are covered by animpermeable polymeric material. This branch forms with the secondsuperior section a tubular wall, which is impermeable to blood flow,while the other branch of this bifurcation is not covered by theimpermeable material, it forms a short permeable and when the bloodflows.
 7. Fenestrated asymmetric intracardiac device, according to whatis stated in claims 1, 2, 3, 4, 5 and 6, this device is characterized bya mesh material which defines its sections. This mesh is made of linkedmetallic threads, forming a deformed mesh, which can acquire itsoriginal shape and dimensions when its deforming action is released. Theimpermeable polymeric material is the polytetrafluorothyelene (PFTE).